Network Working Group M. Mealling
Request for Comments: 3061 Verisign
Category: Informational February 2001
Obsoletes: 3001A URN Namespace of Object Identifiers
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2001). All Rights Reserved.
Abstract
This document describes a Uniform Resource Name (URN) namespace that
contains Object Identifiers (OIDs). It obsoletes RFC 3001.
1. Introduction
An Object Identifier is a tree of nodes where each node is simply a
sequence of digits. The rules roughly state that once an entity is
assigned a node in the Object Identifier (OID) tree, it has sole
discretion to further subdelegate sub-trees off of that node. Some
examples of OIDs include:
o 1.3.6.1 - the Internet OID
o 1.3.6.1.4.1 - IANA-assigned company OIDs, used for private MIBs
and such things
o 1.3.6.1.2.1.27 - The Applications MIB
o 0.9.2342.19200300.100.4 - Object ID's used in the directory pilot
project to identify X.500 Object Classes. Mostly defined in RFC1274.
This document specifies the "oid" URN namespace [2]. This namespace
is for encoding an Object Identifier as specified in ASN.1 [3] as a
URI. RFC 3001 [1] is obsoleted by this specification.
The namespace specification is for a formal namespace.
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RFC 3061 OID URN Namespace February 20012. Specification Template
Namespace ID:
"oid" requested.
Registration Information:
Registration Version Number: 1
Registration Date: 2000-04-30
Declared registrant of the namespace:
The ISO/IEC Joint Technical Committee 1 - SubCommittee 6
The real authority is the ASN.1 specification itself but SC6 is
the committee that has the authority to interpret what that
means, thus that committee is listed as the registrant.
Declaration of structure:
The NSS portion of the identifier is based on the string encoding
rules found in RFC 1778 Section 2.15 [4] which specifies a series
of digits separated by a period with the most significant digit
being at the left and the least significant being at the right.
At no time shall the NSS portion of the URN contain the human
readable description of a particular node in the OID tree. The
NSS portion of the name is strictly limited to the digits 0-9 and
the '.' character with no leading zeros. No other characters are
permitted. This is all expressed in the following ABNF:
oid = number *( DOT number )
number = DIGIT / ( LEADDIGIT 1*DIGIT )
LEADDIGIT = %x31-39 ; 1-9
DIGIT = %x30 / LEADDIGIT ; 0-9
DOT = %x2E ; period
No changes are anticipated since Object Identifiers are fairly
simple and have been standardized with no changes for many years.
Relevant ancillary documentation:
Relevant documentation can be found in X.660/Amd 2 | ISO/IEC
9834-1/Amd 2[3].
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RFC 3061 OID URN Namespace February 2001
Identifier uniqueness considerations:
The rules for assignment of OIDs requires that each OID be unique
to the OID space and that it cannot be reassigned or reused. By
reference this URN namespace inherents those rules.
Identifier persistence considerations:
The rules concerning the use of OIDs requires that they not be
reused once assigned. By reference this URN namespace inherents
those rules.
Process of identifier assignment:
Once an OID is assigned to some entity, that entity can then
create and assign new OIDs below that particular OID. There are
multiple entities that assign new OIDs to the general public. The
top three levels are pre-assigned as follows:
0 - ITU-T assigned
1 - ISO assigned
2 - Joint ISO/ITU-T assignment
several assigned OIDs that are of importance to the Internet are:
1.3.6.1 - the Internet OID
1.3.6.1.4.1 - IANA-assigned company OIDs, used for private
MIBs and such things
Process of identifier resolution:
At this time no resolution mechanism is defined.
Rules for Lexical Equivalence:
OIDs are composed of multiple occurrences of digits and the "."
character. Lexical equivalence is achieved by exact string match.
Conformance with URN Syntax:
There are no additional characters reserved.
Validation mechanism:
None.
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RFC 3061 OID URN Namespace February 2001
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Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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